1. Field of the Invention
The present invention relates to monitoring and controlling high blood pressure by the stimulation of the human body's own baro-receptors with electromagnetic or ultrasonic wave energies.
2. Description of the Prior Art
Hypertension or abnormally high arterial blood pressure is a serious health hazard. Hypertension is the leading cause of cerebrovascular accidents (stroke) and is a major risk factor for coronary artery disease and myocardial infarction (heart attack) as well as heart failure and renal damage. More than 50 million Americans had hypertension according to estimates in 1983.
The treatment of high blood pressure by the prior art is by medications such as calcium blockers, these agents tend to relax the smooth muscle around the arteries. Other medications are beta-adrenergic blockers, which block the release of certain type of chemicals that produce muscle spasms of the arteries, resulting in high blood pressure. Yet other types called ACE inhibitors exert their blocking effect on hormones secreted by the arteries of the kidney that causes spasms of the smooth muscle surrounding the blood vessels. Diuretics have been used in the treatment of hypertension by enhancing the excretion of sodium by the kidneys and thereby reducing the effective blood volume and blood pressure. Other anti-hypertensive agents act by depleting or inhibiting the effect of neuro-transmitters such as norepinephrine either in the central or peripheral nervous system. All such treatments are expensive and generally have many side effects. In addition medication has to be taken at least once a day and often in combinations for long durations and thus become an expensive proposition.
Blood pressure control is related to the caliber and responsive of the blood vessels. Blood pressure is controlled by the chemo-receptors as described above and baro-receptors. In certain instances, such as, during exercise and in stressful situations the body produces higher blood pressure. Here epinephrine, nor-epinephrine corticosteroid are secreted from the adrenal glands. Other hormones are secreted by other endocrine glands. These hormones exert their influence on the motor end plate of the smooth muscle surrounding the arteries and cause the arteries to contract, thus increasing the blood pressure. The motor end plates contain and release chemical compounds that cause the contraction or relaxation of the smooth muscle surrounding the arteries. These are called chemo-receptors. The body also has a protective mechanism called baro-receptors such as those situated at the bifurcation of each of the two carotid arteries. These baro-receptors are activated by high blood pressure. The high blood pressure will stretch nerve endings at the baro-receptors and send electric impulses to relax the smooth muscles surrounding the blood vessels. There are many baro-receptors scattered throughout the arterial system.
Hardening of the arteries also causes high blood pressure. The hardening is called atherosclerosis. It is postulated that the arteries go into spasm off and on for years, then the arteries lose their elasticity and become hard or rigid, thus causing permanent high blood pressure. These arteries do relax by the effect of medications on the chemo-receptors. These hardened arteries also are relaxed by baro-receptors. In certain cases high doses of drugs are given to relieve the effects of severe hardening of the arteries.